howard



, 2 SheetsSheet 2. J. HOWARD & E. T. BOUSFIELD.

STEAM BOILER.

Patented July 9,1867.

cn. Pnomuuo., wAsrumaroN. D. c.

@einen "tetra stent @Hirt J AMES HOWARD AND- E. TENNEY BOSF-IELD, OF BEDFORD, ENGLAND. Letters Patent o. 66,590. dated July 9, 1867; patented in England, January 11, 1867.

llgstbehule referenti in these mints prima ma making part tf its' same.

To ALL WHOM 1T MAY CONCERN;

Bc it known that we, JAMES HOWARD, of Bedford, in the county of Bedford, Agricultural Engineer, and EDWARD TENNEY BOUSFIELmCofthe same place, Engineeiyhave invented Improvements in Tubular Steam- Boilers and we do hereby declare that the following is a full and exact vdescription of ousaid invention.

This invention relates to-improvements ou the tubular boiler, for whi'clrj.- we obtained an American patent, bearing date October 23, 1866, the object being, irst, to provides. moreeective circulation of the water in the vertical tubes of the various sections 'of the boiler, and thereby to prevent or materially retard incrustatiomof the tubes; secondly, to provside a simple and secure waterftight joint between the transverse water tubes and the vertical tubes; thirdly, to strengthen the transversepipes upon whichthe -vertical tubes are set; and,

fourthly, to simplify the construction of the furnace and lues.4 In the accompanying drawing- Figure 1 is a plan view ofthe improved boiler.

Figure 2 is a transverse sectional elevation of the same; and" Figure 3 is apartial sectional elevation on an enlarged scale of a portion of one of the-groups of tubes.

v:A Animatie-vertical tubesfconneoted-tcgcther -inrgroupsat-bettomr-hy-trensvers`e^`pipes B B, and at top by transverse pipes C C; and the groups ,are connected 'together at bottom by short pipes D D, and at top by a longitudinal steam pipe, E. In order to quicken the circulation of the water, We insert internal tubes F, of peculiar construction, in the vertical tubes A, and use them as channels for conducting dowuthe upper portion of the waterk in the boiler to the horizontal pipes, which connect with the lower ends of the .vertical tubes, and constitute, with a. given .length of the' tubes A, the water space of` the boiler. These inner tubes we x in a concentric position in-the main vertical tubes, and cause them to rest on the bottomof the horizontal tubes, as shown best at tig. 3. The internal tubes F we make long enough to reach to the highest water level of the boiler, and their upper ends, which are open, we slit, as shown at iig. 2, or pierce laterally to a distance a little below the lowest water level of the boiler. The lower ends of the tubes F we form so that the water will have a free passage out at the bottom of the tubes. The elect of this arrangement will be to create a. downward current of the water at or near the water level, (notwithstanding the variation :in that level,) through the internal tubes, as indicated by the arrows in iig. 3, and a consequently-increased upward current outside those tubes. The deposit, therefore, while the boiler` is in action, of earthy and saline particles contained in the water, and the consequentl incrustation of the boiler, will be greatly retarded, if not entirely prevented. In order to insure tightness in thebottonrjoints ofthe vertical tubes, we form the annular recesses of the lower transverse pipes in which the vertical tubes are seated of a tapered or V sectionor with one of the'sides ofthe recess inclined, as shown at a a, lig. 3.` The holding bolts will then, as they are screwed tight, draw down the tubes into a contracted space, and cause close contact between the abutting surfaces. The like result may be obtained by tapering the end ofthe tubes, and' making the annular recesses square in cross-seotion, and of somewhat less width than the full thickness of Athe tube, as shown at b b in the same figure. In order to strengthen the transverse pipes B without materially adding to their weight, we cast them with internal divisions c c, through the lower part of which is a hole to allow of the free circulation of the water. Instead of encasing the boiler thus constructed, as heretofore, with independent walls of brick-work, we propose to ll the spaces between the outer tubes with fire-bricks, Amoulded to suit the shape of the spaces to be lled in, as shown at d d, iig. 1. We are thus enabled, by the use of a minimum of material, to form the furnace walls, and at the same time to save space, thereby obtaining important advantages in the setting up of the boiler, niere especially when it is adapted to marine purposes. The lire-bars may be supported bylbrick-work, or in any approved'manner; and when the fire-place is divided, as shown in the drawing, we propose to form the dividing wallof water-tubes, filling in the spaces with iire-brick or other blocks, as when forming the outer walls. The fire and ash-pit doors will be applied in the ordinary manner, the blocks being moulded to suit thevspaces to be filled between the'frames of the doors and the tubes. When we wish to divide the heating-chambers horizontally, so as to return the current of heated gases, :ve castV collars or bands onthe tubes, as shown at e e in iig. 2, which form supports for Athe dividing bricks or plates.

Having now set forth the nature of our invention of improvements in ytubular steam'iboilers, we wish it to be understood that we are aware of inner tubes having been proposed for quickening the circulation of water in the vertical tubes of boilers, such tubes being closed at the bottom and lled with water; but in the arrangement of these inner tubes, so far as we are-aware, no provision has been made for the circulation of the water throughout the whole depth of the water space. In our arrangement, the outer tube communicates with the 1 Steamvand water spaces at'top and bottom, and provision is made in the internal tube for a. differential water level. We do not, therefore, claim the use of inner tubes, of whatever construction, for promoting the circulation of the water; but we cla-im as of our invention- 1. The inner tubes F, provided with the' slitsnear their tops, whereby the differential water level is obtained, in combination with the transverse pipes B, containing internal divisions c, asherein described, for the purpose specified.

2A` Securing a. water-tight joint between the tubes and transverse pipes, in the manner above described.

3. The re-bricks d al, constructed as described, when employed to fill the spaces between the outer tubes B, as herein 4set forth, for the purpose specified. p

In witnesswhereof, we, the said JAMES HOWARD and, EDWARD TENNEY BoUsriELn, havevhereunto' set our hands and seals, the eighteenth dny of March, in the yeanof our Lord one thousand eight hundred and sixty-seven. JAMES HOWARD. [1.. 5.] EDWARD TENNEY BOUSFIELD.` [1.. 5.]

Witnesses: i

FRED.` WALLSDEN, 6'6 Cham-ery Lane, London. M. WYNN, 24 Royal Exchange, London. 

